Patch Name: PHKL_11996

Patch Description: s700 10.01 MP Fix for low %idle, CPU stealing, SCHED_NOAGE

Creation Date: 97/09/05

Post Date:  97/09/11

Hardware Platforms - OS Releases:
	s700: 10.01

Products: N/A

Filesets:
	OS-Core.CORE-KRN

Automatic Reboot?: Yes

Status: General Release

Critical: No

Path Name: /hp-ux_patches/s700/10.X/PHKL_11996

Symptoms:
	PHKL_11996:

	Resource-intensive processes (such as an Informix oninit)
	either perform poorly over time (as timeshare) or
	monopolize the system (as realtime).

	Also, MP systems show processes frequently being moved
	from one CPU to another.

	PHKL_9401:
	Lightly loaded MP systems would show a low %idle.

Defect Description:
	PHKL_11996:

	The scheduling policies available prior to this patch did
	not have a provision for a fixed-priority timeshare
	(non-realtime) process, one which could use many system
	resources without being degraded to a very low priority.
	This patch provides this "no aging" timeshare facility
	for applications which need it.  This facility uses
	the same interface which is in 11.00, through the POSIX
	interface routines: applications which need to use this
	facility should use the sched_setscheduler(2) system call
	with a new policy of 8 (to be defined in 11.00 as
	SCHED_NOAGE).

	Idle processors were stealing processes from other run
	queues, even when those processes were running frequently
	already.

	PHKL_9401:
	On MP systems, the idle() loop algorithm was too aggressive.
	All the idle processors would spinlock to get access to the
	run queues of the busy cpus.

SR:
	5003346163 5003360446 5003380113

Patch Files:
	/usr/conf/lib/libhp-ux.a(pm_policy.o)
	/usr/conf/lib/libhp-ux.a(pm_rtsched.o)
	/usr/conf/lib/libhp-ux.a(pm_swtch.o)

what(1) Output:
	/usr/conf/lib/libhp-ux.a(pm_policy.o):
		pm_policy.c  $Date: 97/08/19 22:44:42 $ $Revision: 1
			.2.71.36 $ PATCH_10.01 (PHKL_11996)
	/usr/conf/lib/libhp-ux.a(pm_rtsched.o):
		pm_rtsched.c $Date: 97/08/01 14:26:51 $ $Revision: 1
			.2.71.14 $ PATCH_10.01 (PHKL_11996)
	/usr/conf/lib/libhp-ux.a(pm_swtch.o):
		pm_swtch.c    $Date: 97/08/19 22:38:04 $ $Revision:
			1.2.71.49 $ PATCH_10.01 (PHKL_11996)

cksum(1) Output:
	2181840720 13728 /usr/conf/lib/libhp-ux.a(pm_policy.o)
	243827986 8884 /usr/conf/lib/libhp-ux.a(pm_rtsched.o)
	1065243033 19320 /usr/conf/lib/libhp-ux.a(pm_swtch.o)

Patch Conflicts: None

Patch Dependencies: None

Hardware Dependencies: None

Other Dependencies: None

Supersedes:
	PHKL_9401

Equivalent Patches:
	PHKL_11997:
	s800: 10.01

	PHKL_12039:
	s700: 10.10

	PHKL_12041:
	s800: 10.10

	PHKL_12042:
	s700: 10.20

	PHKL_12043:
	s800: 10.20

Patch Package Size: 100 KBytes

Installation Instructions:
	Please review all instructions and the Hewlett-Packard
	SupportLine User Guide or your Hewlett-Packard support terms
	and conditions for precautions, scope of license,
	restrictions, and, limitation of liability and warranties,
	before installing this patch.
	------------------------------------------------------------
	1. Back up your system before installing a patch.

	2. Login as root.

	3. Copy the patch to the /tmp directory.

	4. Move to the /tmp directory and unshar the patch:

		cd /tmp
		sh PHKL_11996

	5a. For a standalone system, run swinstall to install the
	    patch:

		swinstall -x autoreboot=true -x match_target=true \
			-s /tmp/PHKL_11996.depot

	5b. For a homogeneous NFS Diskless cluster run swcluster on the
	    server to install the patch on the server and the clients:

		swcluster -i -b

	    This will invoke swcluster in the interactive mode and
	    force all clients to be shut down.

	    WARNING: All cluster clients must be shut down prior to the
		     patch installation.  Installing the patch while the
		     clients are booted is unsupported and can lead to
		     serious problems.

	    The swcluster command will invoke an swinstall session in which
	    you must specify:

		alternate root path  -  default is /export/shared_root/OS_700
		source depot path    -  /tmp/PHKL_11996.depot

	    To complete the installation, select the patch by choosing
	    "Actions -> Match What Target Has" and then "Actions -> Install"
	    from the Menubar.

	5c. For a heterogeneous NFS Diskless cluster:

		- run swinstall on the server as in step 5a to install
		  the patch on the cluster server.

		- run swcluster on the server as in step 5b to install
		  the patch on the cluster clients.

	By default swinstall will archive the original software in
	/var/adm/sw/patch/PHKL_11996.  If you do not wish to retain a
	copy of the original software, you can create an empty file
	named /var/adm/sw/patch/PATCH_NOSAVE.

	Warning: If this file exists when a patch is installed, the
	         patch cannot be deinstalled.  Please be careful
		 when using this feature.

	It is recommended that you move the PHKL_11996.text file to
	/var/adm/sw/patch for future reference.

	To put this patch on a magnetic tape and install from the
	tape drive, use the command:

		dd if=/tmp/PHKL_11996.depot of=/dev/rmt/0m bs=2k

Special Installation Instructions: None